Thread rolling machine



Jan. 14, 1964 R. D. MORTON E1- AL 3,117,473

THREAD ROLLING MACHINE 5 Sheets-Sheet 1 Filed July 19, 1960 INVENTORS ROBERT D. MORTON B EDWARD GI GEO/10$ WTTO NEYS Jan. 14, 1964 THREAD ROLLING MACHINE A? FIG. 2

' INVENTORS ROBERT 0. MORTON BYED WA R0 6. (mo/106m ATTO EYS R. D. MORTON ET AL 3,117,473

Jan. 14, 1964 R. D. MORTON ETAL THREAD ROLLING MACHINE Filed July 19, 1960 5 She etsSheet 3 Jan. 14, 1964 Filed July 19, 1960 FIG. 4

R. D. MORTON ET AL THREAD ROLLING MACHINE 5 Sheets-Sheet 4 INVENTORS ROBERT D. MORTON ED WARD G. GROHOSK/ ATTOR 5Y5 R. D. MORTON ETAL THREAD ROLLING MACHINE Jan. 14, 1964 5 Sheet s-Sheet 5 Filed July 19, 1960 FIG. 5 M9 63 INVENTORS ROBERT D. MOR N EDWA PD GGPOHO$KI 2 ATTOR EYS nite States atent Ofiice 3d 37,473 Patented Jan. 14, 'ld fid- 1 3,117,473 THREAD RGLLENG MACIHNE Rohcrt D. Morton, West Hartford, and Edward G. Grohoski, Torrington, onn., assignors to The Herb ford Special Machinery Qompany, Simshury, t'lona, a corporation of Connecticut Filed .hily 19, 1960, Ser. No. 43,816 4 Claims. (65. 8ll--8) This invention generally relates to thread rolling machines and is more particularly directed to an improved thread rolling machine of the fiat die reciprocating type.

It is a primary object of this invention to provide an improved flat die thread rolling machine of the reciprocatin type having greatly increased operating speeds without sacrifice of accuracy or reliability.

It is a further object of this invention to provide an improved thread rollin machine of the type described having an improved work blank feed control and starter mechanism.

It is a still further object of this invention to provide an improved high speed, fiat die thread rolling machine of the reciprocating type that is economical to manufacture, durable in operation and easily adjusted to accommodate a wide variety of work blanks.

Gther objects will be in part obvious and in part pointed out more in detail hereafter.

Th invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application which will be indicated in the appended claims.

in the drawings:

FIG. 1 is a front elevation view of a preferred embodiment of the thread rolling machine of this invention;

FIG. 2 is a side elevation view of the thread rolling machine of PEG. 1;

FIG. 3 is a partial top plan view of the table and operating mechanism;

FIG. 4 is an enlarged fragmentary view of the control mechanism of FIG. 3; and

FIG. 5 is enlar ed partial cross section View of the drive mechanism taken generally along the line 5-5 of FIG. 3.

As best seen in GS. l, 2 and 3, a preferred embodiment of this improved thread rolling machine generally comp .cs 21 frame iii having mounted thereon a hopper 12- for receiving a large quantity of work blanks, a table surface or bed 13- inclined to the horizontal, a feed mechanism 15 for conveying blanks from the hopper 12 to a pair of thread rolling dies, fixed die 17 and movable die 13., a work blank control mechanism generally designated 2t a drive mechanism generally designated 21. To further assist in understanding the hereinafter de scribed details of this invention, it is noted that the work blanks are discharged from the hopper 12 into the feed mechanism 35 for travel to a position adjacent the fixed die 1?. Discharge of a selected Work blank from the feed mechanism 15 and proper positioning thereof between the dies 17 and 18 is effected by control member 2%, which member and movable die 18 are driven and controlled from a common power source.

As best ecn in FIG. 1, frame it is conveniently made in a desk like manner to provide a knee hole opening 11 so that the machine operator can comfortably sit in front of frame 1%, if so desired, with the table surface 13 mounted thereon and inclined upwardly away from the operators position at an angle or" approximately 30. Pedesta 22 of frame it houses and supports drive motor 23 (shown in dotted lines) which is arranged to supply mechanical power to the machine as hereinafter described.

Turning now to the details of the operating mechanism and particularly FIG. 3, it is noted that fixed or stationary die 17 is removably mounted on stationary die block 25 by clamp 26 and that block 25 is secured to table 13 by fasteners 28. Block 25 is provided with positioning abutments 2% which cooperate with clamp 26 and block 25 to position stationary die 17 with its work surface 3d perpendicular to table 13. Main slide housing 31 is adjustably positioned on table 133 by a .pair of adjusting screws 33 and fixedly secured to table 13 in any desired manner (not shown) after adjustment. Cover member 35 is secured to housing .31 by fasteners 36 and cooperates With housing 31 to define a groove which supports and guides main slide 38. Slide 38, in turn, is provided with clamps 4i and 41 for removably mounting movable die 18 in a position with its work surface 43 spaced from, but generally parallel to the working surface of stationary die 17.

in order to effect reciprocating movement of movable die 18 relative to fixed die 17, there is provided a crank wheel 5t which, as best seen in FIG. 5, is mounted on splined shaft 52 journallcd in bearings 53 and 5d supported in cover member 56 and table 13', respectively. Rotational power is supplied to shaft 52 through bevel gear 57 secured to shaft 52 and bevel gear 58 journalled in table 13 and driven by motor 23 through a belt-type speed change mechanism generally designated 59 (see FIG. 1). Crank wheel 50 and main slide 38 are interconnected by pitrnan or connecting rod dil having one end thereof pivotally secured to slide 38 at 62. and having its other end pivotally connected to crank wheel 50' at point 63 s aced from shaft 52. The mode of connection of rod 6 to crank wheel 50 is hereinafter described in greater detail, but it is noted at this point that, under operating conditions, this connection functions as a simple pivot point so that rotation of crank wheel 5G: by motor 23 through drive mechanism 59/ causes main slide 38 and movable die 18 to reciprocate relative to fixed die 17.

The feed mechanism f the illustrated preferred embodiment is designed for use with headed work blank and is, accordingly, provided with a pair of spaced apart feed tracks or rails 66 and 6? extending from the discharge end 7d of rotatable hopper 12 to a point adjacent the sta ting end 72 of fixed die 1'7. In order to accommodate headed blanks of different shapes and sizes, head guide 68 is adjustably mounted on brackets 7d and 75 in a position spaced above but parallel to rails 66 and 67. While not essential to the present invention, it is noted that drum 12. can be rotated in any desired manner and is provided with a feed wheel 77 to insure proper discharge of work blanks therefrom. The rails 66 and *7 are spaced apart by an amount sufiicient to accommodate the body of a single work blank so that a single work blank is positioned at the discharge end of the feed rails and the inclined mounting of the rails permits gravity feed of the blanks.

The control mechanism generally designated 20 serves as a gate for automatically opening and closing the discharge end of the feed rails so as to admit a single work blank into position between the starting end of each die and acts as a starting finger to wedge the selected blank between the starting ends of the dies so that, upon movement of the movable die relative to the fixed die, the desired thread is accurately rolled onto the outer periphery of the blank. in order to effect this control action, mechanisin 29 includes a control arm 84 pivotally mounted at point 82 on table 13 for movement in a plane parallel to table 13 and perpendicular to the working surface of the dies. Finger 83 is mounted at the end of arm by an assembly generally designated 9,4, which assembly accommodates adjustable positioning of finger 83 in a plane perpendicular to table 13 through the cooperating action of threaded fastener 35 and T plates 86 and 87 and accommodates adjustable positioning of finger 83 along a line extending longitudinally therethrough through the cooperation of fastener 83 and slot 89. In order to limit the counterclockwise movement of arm ill (as viewed in FIG. 4), there is provided a stop member 9t), mounted on stationary die block 25, and a cooperating stop member 91, mounted on abutment 92 on arm 8%). Ann 84) is provided with an oifset end 93 so that even though pivot point 82 is generally in alignment with the starting end 72 of fixed die 17, finger 83 is positioned substantially parallel to the working faces of die members 17 and 18 and substantially perpendicular to the discharge end of feed rails 66, 67 when stop members 9t) and 91 are in engagement. Additionally, finger 83 is of such a length so that it extends between the opposed surface of dies 17 and 18 a sufficient amount to insure proper starting of the work blank between the dies when stop members 9%) and 91 are in engagement.

Oscillatory movement of arm lid in proper timed relationship to the oscillatory movement of movable die .18 is accomplished by mounting (see FIGS. 3 and an annular cam 95 about the outer periphery of drive wheel 58 by clamps generally designated 96 (one of which is shown in FIG. 5). Arm 80 moves in accordance with the shape of cam 95 through the use of follower lever $8 pivotally supported at point 99 on mounting lever 106 and connected to arm till by adjustable connecting link 1&2 pivotally secured at its ends to arm 30 and lever 93. Spring 195 is connected between point 166 on table 13 (beneath arm 80 in FIG. 3) and point 197 of lever 98 so as to urge lever 98 in a clockwise direction, thereby urging arm 8t) towards the position determined by stop members 9t and 91 and urging cam roll res mounted on end 110 of follower lever 93 into engagement with the outer periphery of cam 95. It is noted at this point that cam 95 of the illustrated embodiment, while generally circular, is provided with a surface having a high point or position of maximum radius 95 which forces lever 98 counterclockwise and arm $0 clockwise to open the discharge end of feed rails 66, 67 and discharge a work blank during movement of die 18 away from die 17. Subsequent to discharging the blank, roll 11:79 passes the low point or point of minimum radius of the cam to permit spring 1% to move arm 80 to the position shown in FIG. 3, thereby to wedge a work blank between the starting edges of the dies.

In order to permit operation of the crank wheel and movement of the dies without discharging workpieces from the feed rails such as during set-up operations, it is noted that mounting lever 19% is pivotally mounted at point 112 with end portion 114 positioned between stop 116 and cam 117, both of which are mounted on table 13 within housing 1155. Cam 117 is pivotally mounted on shaft 119 and controlled in position by arm 12% so that rotation of arm 12% to the position shown in FlG. 3 locks end portion 114 between stop 116 and cam 117 to fix pivot point 99 in position. Upon rotation of control arm 12b in a clockwise direction, extending portion 114 of mounting lever 1th is free to pivot about point 112 under the influence of spring 1%, thereby shifting pivot point to move cam roll 199 out of engagement with cam 95 with control arm 30 in the closed gate position and stop members 91) and 91 in engagement.

To facilitate die-matching adjustment of moving die 18 to stationary die 17 during machine set-up, the pivot connection 63 of connecting rod so with crank wheel 50 is made adjustable. As best seen in FIG. 5, connection 63 includes a pivot pin 125 having its lower end 126 journalled in wheel 59 by bearing 127 and having its upper end 128 eccentrically arranged relative to its lower end and extending through an aperture in connecting rod 69. Mounted at the upper end of eccentric portion 128 is a gear 129 (preferably formed integrally therewith) which engages pinion 131 rotatably mounted in rod 60. Rotation of pinion 131 by inserting a wrench into the hexagonal socket formed therein rotates gear 129 so as to shift eccentric portion 123 relative to rod 66 while rotating end 126 of pin in bearing 127. Thus, the position of rod 69 relative to crank wheel 5'0 can be adjusted. When in the desired position, fastener 133 can be tightened to fix the position of eccentric portion 123 of pin 125 relative to rod 6% To effect timing adjustment of the movement of die 18 relative to the movement of finger 83, cam 5 can be rotated relative to crank wheel 56 by releasing clamps 96. Upon achieving the desired cam setting, clamps 9 are tightened to secure cam 95 to wheel 5% while at the same time, fixing the timed relationship for the desired operating speed.

As most clearly seen in FIGS. 1 and 2, the speed change knob 14%) for the motor drive mechanism, the control button console 141 for controlling the energization of the motor and oscillatory drive units, the lock-out control arm 126 for the feed mechanism as well as other control features are easily accessible at the front of the machine so as to simplify control. and operation thereof, particularly by an operator sitting before the machine as if it were a desk. The cover 143 is secured to table 13 in any desired manner to protect the operator from injury by the rotating crank wheel and associate parts, and a discharge chute 143 is mounted on table 13 to guide the finished work blanks to a tote box generally designated 144.

A typical operating cycle of the illustrated machine embodying this invention involves loading the rotary hopper 12 with the desired number of work blanks so that the feed mechanism generally designated '77 will supply work blanks, one at a time, for travel down the feed rails 66, 67 to a point adjacent the starting edge of die 17, the discharge end of the feed rails being closed by gate finger S3. Motor 23 is energized by actuation of the appropriate switch on console 141 to rotate crank wheel 59 thereby oscillating main slide 38 and die 13 in a direction parallel to the longitudinal axis of the die members. As suming that crank 12% is now rotated to the position shown in FIG. 3, follower roll 199 on lever 98 is brought into contact with cam 95 under the force of spring 195 so that, at the appropriate time as determined by the position of the high point of cam relative to the pivot axis of connecting rod 60, control arm 80 and finger 83 move in a clockwise direction so as to permit a work blank to slide into position against movable die 13 and adjacent the starting end 72 of stationary die 17. Continuing rotation of crank wheel 5% causes follower lever 98 to pivot about point 99 under the influence of spring 1115 so that the leading edge of finger 33 positions the work blank and assists in properly wedging the work blank between the leading edges of the dies. If desired, and as seen in FIG. 4, finger 83 can be provided with a lower stop projection 145 to support and position the lower end of the work blank. It is noted at this point that the movement of control arm 89 as determined by cam surface 9:? of the preferred embodiment is in the nature of 2 /2" to 3 and that finger $3 is substantially perpendicular to a radius extending between the pivot point 82 of arm tit and the starting end of die 17 when stop members 9:"; and and 91 are in engagement. This limited arc of movement and the constructional arrangement insures that there will be no interference of the control mechanism generally designated 20 with the relatively moving dies. As crank wheel 50 continues to rotate, arm 80 remains in the position determined by the stop and the spring 1% and the threads are rolled on the blank in a conventional manner.

It is noted that the inclined arrangement of table 13 not only facilitates easy operation of the machine by an operator, but also permits the work blanks to be fed by gravity and to arrive at the face of the moving die in proper angular orientation without any substantial changes in direction which would slow the feed rate of the machine. By arranging the feed rails generally perpendicular to a plane passing through the work face of either die, as well as the pivoted arrangement of the control member 89, a single finger can be operated as a gate for the feed rails as well as a starting finger.

In the preferred embodiment substantially all of the moving parts are made of lightweight metals such as aluminum, where possible, so as to reduce the inertia of the various components and further facilitate highspeed operation of the machine.

From the foregoing description of the construction and operation of a preferred embodiment of this invention, it is apparent that there has been provided a novel mechanism for operating and controlling a fiat die reciprocating type thread rolling machine, which mechanism is especially reliable, easily adjusted and manufactured, and extremely accurate in operation while permitting much higher operating speeds.

As will be apparent to persons skilled in the art, various modifications and adaptations of the structure above described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims.

We claim:

1. A thread rolling machine of the reciprocating type comprising a frame, a first thread rolling die fixedly mounted on said frame with its working surface laterally inclined relative to a horizontal plane passing therethrough and oriented for work blank movement in a substantially horizontal direction, a second thread rolling die, means mounting said second die in spaced relationship to said first die and for movement substantially parallel thereto, means for feeding work blanks to a position adjacent the starting end of said first die, a finger for gating said means for feeding work blanks and wedging a work blank between the starting ends of said first and said second die, means mounting said finger on said frame solely for arcuate movement, a crank wheel rotatably mounted on said frame, a connecting rod having one end pivotally connected to said crank wheel at a point spaced from the axis of rotation thereof and having its other end pivotally secured to said second die, a cam surface on said crank wheel, a cam follower pivotally mounted on said frame, one end of said cam follower being engageable with said cam surface, the other end of said cam follower being pivotally connected to the means mounting said finger, and means for rotating said crank wheel.

2. A thread rolling machine of the reciprocating type comprising a frame, a first thread rolling die fixedly mounted on said frame with its working surface laterally inclined relative to a horizontal plane passing therethrough and oriented for work blank movement in a substantially horizontal direction, a second thread rolling die, means mounting said second die in spaced relationship to said first die and for movement substantially parallel thereto, means for feeding work blanks to a position adjacent the starting end of said first die, a finger for gating said means for feeding work blanks and wedging a work blank between the starting ends of said first die and said second die, means mounting said finger on said frame solely for arcuate movement and common drive means for reciprocating said second die relative to said first die and for arcuately moving said finger.

3. A thread rolling machine of the reciprocating type comprising a frame having a table surface thereon inclined relative to a horizontal plane passing therethrough, a first thread rolling die fixedly mounted on said frame with its working surface substantially perpendicular to said table surface and oriented for work blank movement in a substantially horizontal direction, a second thread rolling die, guide means mounting said second die in spaced relationship to said first die and for movement parallel to said second die and said table surface, a pair of straight feed rails mounted parallel to said table surface and terminating adjacent the starting end of said first die to feed work blanks thereto, a control member mounted solely for arcuate movement at one end thereof on said table surface and spaced from said first die, said control member being movable in a plane generally parallel to said table surface and having a finger fixed on the other end thereof, said control member being operable to move said finger from a position generally parallel to and intermediate said first die and said second die wherein said finger closes the discharge end of said feed rails to a position remote therefrom to discharge a work blank so that whereafter reverse movement of said control membcr causes said finger to wedge a work blank between the starting ends of said first die and said second die, common drive means rotatable about an axis generally perpendicular to said ta'ble surface for reciprocating said second die relative to said first die and for pivoting said control member.

4. A thread rolling machine of the reciprocating type comprising a frame, a first thread rolling die fixedly mounted on said frame with its working surface laterally inclined relative to a horizontal plane passing therethrough and oriented for work blank movement in a substantially horizontal direction, a second thread rolling die, means mounting said second die in spaced relationship to said first die and for movement substantially parallel thereto, means for feeding work blanks to a position adjacent the starting end of said first die, a finger for gating said means for feeding work blanks and wedging a work blank between the starting ends of said first and said second die, means mounting said finger on said frame solely for arcuate movement a crank wheel rotatably mounted on said frame, a connecting rod having one end pivotally connected to said crank wheel at a point spaced from the axis of rotation thereof and having its other end pivotally secured to said second die, a cam surface on said crank wheel, a cam follower pivotally mounted on said frame, one end of said cam follower being engageable with said cam surface, the other end of said cam follower being pivotally connected to the means mounting said finger for arcuate movement, means for shifting the pivot point of said follower to disengage said follower from said cam surface, and means for rotating said crank wheel.

References Cited in the file of this patent UNITED STATES PATENTS 1,104,091 Wilcox July 21, 1914 1,696,225 Blood Dec. 25, 1928 1,773,539 Miller Aug. 19, 1930 1,798,920 Wilcox Mar. 31, 1931 2,309,126 Lundius Jan. 26, 1943 2,672,774 Stern Mar. 23, 1954 2,767,588 Drury Oct. 23, 1956 2,859,647 Nielsen Nov. 11, 1958 OTHER REFERENCES Russian certificate 116,242, Jan. 19, 1959. 

1. A THREAD ROLLING MACHINE OF THE RECIPROCATING TYPE COMPRISING A FRAME, A FIRST THREAD ROLLING DIE FIXEDLY MOUNTED ON SAID FRAME WITH ITS WORKING SURFACE LATERALLY INCLINED RELATIVE TO A HORIZONTAL PLANE PASSING THERETHROUGH AND ORIENTED FOR WORK BLANK MOVEMENT IN A SUBSTANTIALLY HORIZONTAL DIRECTION, A SECOND THREAD ROLLING DIE, MEANS MOUNTING SAID SECOND DIE IN SPACED RELATIONSHIP TO SAID FIRST DIE AND FOR MOVEMENT SUBSTANTIALLY PARALLEL THERETO, MEANS FOR FEEDING WORK BLANKS TO A POSITION ADJACENT THE STARTING END OF SAID FIRST DIE, A FINGER FOR GATING SAID MEANS FOR FEEDING WORK BLANKS AND WEDGING A WORK BLANK BETWEEN THE STARTING ENDS OF SAID FIRST AND SAID SECOND DIE, MEANS MOUNTING SAID FINGER ON SAID FRAME SOLELY FOR ARCUATE MOVEMENT, A CRANK WHEEL ROTATABLY MOUNTED ON SAID FRAME, A CONNECTING ROD HAVING ONE END PIVOTALLY CONNECTED TO SAID CRANK WHEEL AT A POINT SPACED FROM THE AXIS OF ROTATION THEREOF AND HAVING ITS OTHER END PIVOTALLY SECURED TO SAID SECOND DIE, A CAM SURFACE ON SAID CRANK WHEEL, A CAM FOLLOWER PIVOTALLY MOUNTED ON SAID FRAME, ONE END OF SAID CAM FOLLOWER BEING ENGAGEABLE WITH SAID CAM SURFACE, THE OTHER END OF SAID CAM FOLLOWER BEING PIVOTALLY CONNECTED TO THE MEANS MOUNTING SAID FINGER, AND MEANS FOR ROTATING SAID CRANK WHEEL. 